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We report the fabrication and characterization of a plasmonic metasurface comprising electrically-contacted sub-wavelength gold dipole nanoantennas, conformally coated by a thin hafnia film, an indium tin oxide layer and a backside mirror, forming metal–oxide–semiconductor (MOS) capacitors, for use as an electrically-tunable reflectarray or metasurface. By voltage biasing the nanoantennas through metallic connectors and leveraging the carrier refraction effect in the MOS capacitors, our measurements demonstrate phase control in reflection over a range of about 30°, with a constant magnitude of reflection coefficient of 0.5, and the absence of secondary lobes. Comprehensive electromagnetic and quantum carrier models of the structure are developed and are in excellent agreement with the measurements. The metasurface holds promise for use as an optical phased array.

Currently, intravascular optical coherence tomography (IV-OCT) is limited to anatomical imaging, providing structural information about atherosclerotic plaque morphology, thrombus and dissection. Earlier detection and risk stratification would be possible through molecular characterization of endothelium but necessitates a purpose-engineered IV-OCT contrast agent. Here we developed gold superclusters (AuSCs) tailored to clinical instrumentation and integrated into clinically relevant workflows. AuSCs are aqueously dispersible clusters of closely packed small gold nanoparticles, affording plasmon hybridization to maximize light scattering at the IV-OCT laser line (~1,350 nm). A polymer coating fosters AuSC uniformity and provides a functionalizable handle, which we targeted to intravascular P-selectin, an early vascular endothelial marker of inflammation. In a rat model of intravascular inflammation, P-selectin-targeted AuSC facilitated IV-OCT molecular imaging, where the strength of the signal correlates with the severity of vascular inflammation.

Wafer-level testing is an important step for process and quality control of electronic chips in integrated circuit (IC) manufacturing which occurs before packaging. The process of wafer probing in its conventional contacting schemes, becomes more complicated as ICs move to smaller technology nodes and more compact designs, greatly increasing testing costs. Non-contact optical wafer probing can overcome physical probing complications, reducing costs, and increasing throughput and reliability. In this article, a CMOS compatible, broadband (22 GHz), small footprint (5 μm dia.) plasmonic electro-optic modulator of low insertion loss (4 dB) and wide optical working bandwidth (100 nm) is proposed and demonstrated as a potential solution for wafer-level optical testing. The device modulates in reflection an incident optical carrier emerging from an optical fiber in a non-contact arrangement, to work as a data output channel from the wafer. A modulation depth of over 2% is achieved which should be sufficient to meet the requirements of wafer-level testing. The device can be placed anywhere on wafer.

The emission of polar volatile organic compounds (VOCs) is a major worldwide concern of air quality and equally impacts the preservation of cultural heritage (CH). The challenge is to design highly efficient adsorbents able to selectively capture traces of VOCs such as acetic acid (AA) in the presence of relative humidity (RH) normally found at storage in museums (40–80%). Although the selective capture of VOCs over water is still challenging, metal–organic frameworks (MOFs) possess highly tunable features (Lewis, Bronsted, or redox metal sites, functional groups, hydrophobicity, etc.) suitable to selectively capture a large variety of VOCs. In this context, we have explored the adsorption efficiency of a series of MOFs thin films (ZIF-8(Zn), MIL-101(Cr), and UiO-66(Zr)-2CF3) for the selective capture of AA based on a UV/vis and FT-IR spectroscopic ellipsometry in operando study (2–6% of relative pressure of AA under 40% of RH), namely conditions close to the realistic environmental storage conditions of cultural artifacts. For that purpose, optical quality thin films of MOFs were prepared by dip-coating, and their AA adsorption capacity and selectivity were evaluated under humid conditions by measuring the variation of the refractive index as a function of the vapor pressures while the chemical nature of the coadsorbed analytes (water and AA) was identified by FT-IR ellipsometry. While thin films of ZIF-8(Zn) strongly degraded upon exposure to AA/water vapors, films of MIL-101(Cr) and UiO-66(Zr)-2CF3present a high chemical stability under those conditions. It was shown that MIL-101(Cr) presents a high AA adsorption capacity due to its high pore volume but exhibits a poor AA adsorption selectivity under humid conditions. In contrast, UiO-66(Zr)-2CF3was shown to overpass MIL-101(Cr) in terms of AA/H2O adsorption selectivity and AA adsorption/desorption cycling stability because of its high hydrophobic character, suitable pore size for adequate confinement, and specific interactions.

We propose a tunable plasmonic semiconductor laser that exploits loss perturbation as a tuning mechanism. A metal oxide semiconductor (MOS) capacitive structure is added on top of an edge-emitting Fabry-Perot (FP) diode laser, such that a hybrid plasmonic TM mode that overlaps partly with the MOS capacitor and the semiconductor gain region is supported as the lasing mode. We also propose the use of a layer of conductive oxide, e.g., indium tin oxide (ITO), as the semiconductor of the MOS structure, because the epsilon near zero (ENZ) condition can be attained therein under accumulation, thereby producing a very large change in the effective index of the hybrid plasmonic TM mode. The change in the imaginary part of the effective index is used to tune the lasing wavelength - exploiting loss perturbation to achieve laser tuning is paradigm-shifting. The laser proposed operates at telecom wavelengths, requiring an electrical forward bias to pump the active layer, and a gate voltage to drive the MOS tuning capacitor. Simulations yield a tuning range of over 7 nm in the O-band for a $100 \mu \text{m}$ long FP laser cavity.

Surface plasmon polaritons (SPPs) propagating along a waveguide working electrode are sensitive to changes in the local refractive index, which follow changes in the concentration of reduced and oxidized species near the working electrode. The real-time response of the output optical power from a waveguide working electrode is proportional to the time convolution of the electrochemical current density, precluding the need to compute the latter a posteriori via numerical integration. Convolutional voltammetry yields complementary results to conventional voltammetry and can be used to determine the diffusion constant, bulk concentration, and the number of transferred electrons of electroactive species. The theoretical optical response of a waveguide working electrode is derived and validated experimentally via chronoamperometry and cyclic voltammetry measurements under low power SPP excitation, for various concentrations of potassium ferricyanide in potassium nitrate electrolyte at various scan rates. Increasing the SPP power induces a regime where the SPPs no longer act solely as a probe of electrochemical activity, but also as a pump creating energetic electrons and holes via absorption in the working electrode. In this regime, the transfer of energetic carriers (electrons and holes) to the redox species dominates the electrochemical current density, which becomes significantly enhanced relative to equilibrium conditions (low SPP power). In this regime the output optical power remains proportional to the time convolution of the current density, even with the latter significantly enhanced by the transfer of energetic carriers.

We use the end-facet of a solid-core polarization-maintaining photonic crystal fiber (PM-PCF) as a platform on which to fabricate resonant plasmonic nanostructures. Solid-core PM-PCFs can be excited in a polarization-aligned single mode by supercontinuum light, so they are well-suited to the wavelength-interrogation of resonant plasmonic nanostructures, especially supporting complex spectra over a broad spectral range. The nanostructures implemented consist of an array of heptamer-arranged nanoholes formed in a thin Au film. The nanoholes were milled with a He^+ focused ion beam, with the array polarization-aligned in situ to cover the solid core of the PM-PCF. Transmittance spectra, measured using a supercontinuum source coupled to the input of the PM-PCF, reveal a rich set of Fano resonances associated with localized and propagating surface plasmons. The measured spectra are compared to computations in order to identify the resonant modes. The spectra redshift as the medium covering the nanoholes changes from air to oil, anticipating application to sensing.

A deep gold-coated sinusoidal grating is proposed as a transducer for label-free real-time biosensing, operating in a new configuration based on the optical switch effect, which produces complementary optical outputs enabling differential and referenced detection. Biosensing experiments are reported for the first time on this platform, using immunoassays involving biospecific pairs consisting of bovine serum albumin and its antibody, and human serum albumin and its antibody. Direct and sandwich immunoassays are demonstrated along with negative controls. A limit of detection of 6 pg/mm2was obtained. A theoretical model correlating the variation in the differential referenced output optical signal with adlayer growth is presented and supports the experimental results. The proposed detection device operating in the optical switch configuration makes a promising case for point-of-care detection applications because the differential detection of two diffracted orders enables common noise suppression and robust interrogation.

•Kanamycin-tolerant alfalfa rhizobia in agricultural soils•Antibiotic resistance genes within synthetic conjugative plasmids•Genomic studies of putative GMO-free inoculants can improved safety

AbstractObjective:The aim of this research was to determine the changes in medical student attitudes toward nutrition counseling after implementation of a novel curricular activity during a required third-year clerkship.Method:All third-year medical students completing their required family medicine clerkship were invited to participate in a voluntary survey composed of the Nutrition in Patient Care Survey (NIPS) and demographics before their required curricular clerkship activity consisting of two separate case-based modules focused on nutritional aspects of patient care. Students and faculty facilitators met via web platform at an assigned time to review and discuss questions. All students were invited to complete the postsurvey composed of only the NIPS.Results:Completion rate was 31% for both pre- and postsurveys. Students’ intended specialty choice did not lead to a significant difference in scores on any of the five subscales on pre-intervention surveys. Almost half (43.9%) of the students who completed the surveys reported offering nutrition-related counseling despite lack of formal training. The Physician–Patient Relationship score went from 4.29 to 4.37 (p < 0.03) and the Physician Efficacy score went from 3.18 to 3.34 (p < 0.01). The was no significant difference identified pre- versus postintervention for the Clinical Behavior scales.Conclusions:The modules used in this pilot study resulted in positive changes in student attitudes toward counseling patients about nutrition. The inclusion of required case-based modules focused on nutrition is feasible and can positively impact student attitudes regarding their efficacy in counseling patients.

We fabricate plasmonic heptamer-arranged nanohole (HNH) arrays by helium (He) focused ion beam (HeFIB) milling, which is a resist-free, maskless, direct-write method. The small He+beam spot size and high milling resolution achieved by the gas field-ionization source used in our HeFIB allows the milling of high aspect ratio (4:1) nanoscale features in metal, such as HNHs incorporating 15 nm walls of high verticality between holes in a 55-nm-thick gold film. Drifts encountered during the HeFIB milling of large arrays, due to sample stage vibrations or He beam instability, were compensated by a drift correction technique based on in situHe ion imaging of alignment features. Our drift correction technique yielded 20 nm maximum dislocation of HNHs, with 6.9 and 4.6 nm average dislocations along the horizontal and vertical directions, respectively. The measured optical resonance spectra of the fabricated plasmonic HNH arrays are presented to support the fabrication technique. Defects associated with HeFIB milling are also discussed.

Se realizó un estudio epidemiológico molecular en una población de 9.422 donantes de sangre de la provincia de Corrientes (noreste de Argentina), con el fin de determinar la prevalencia del virus linfotrópico T del humano tipos 1 y 2 (human T-cell lymphotropic virus: HTLV-1/2), de identificar filogenéticamente a los subtipos/subgrupos de HTLV-1 y 2 encontrados y de realizar el análisis de mutaciones. Sobre la base de los resultados obtenidos, se demostró que tanto el HTLV-1 como el HTLV-2 se encuentran circulando en una población de bajo riesgo de Corrientes, si bien con una prevalencia similar a las de áreas no endémicas. Los estudios filogenéticos identificaron al subtipo Cosmopolita subgrupo Transcontinental (Aa) del HTLV-1 y al subtipo b del HTLV-2. Los donantes infectados no manifestaron antecedentes de riesgo tales como transfusiones, uso de drogas inyectables ni parejas sexuales de riesgo o seropositivas para HTLV-1/2. Estos resultados indican que estos virus fueron transmitidos de madre a hijo, posiblemente de generación en generación, y que estas cepas fueron introducidas en la población caucásica de esta región a partir de ascendientes originarios de áreas endémicas del país o por contacto producido tiempo atrás con individuos infectados de otros países. Nuestros resultados demuestran por primera vez la presencia de HTLV-1 y HTLV-2 en la provincia de Corrientes. Y si bien se puede considerar a esta provincia como área no endémica, se destaca la necesidad de incluir a estos retrovirus en un programa nacional de salud pública, con el fin de contar con profesionales capacitados para realizar su diagnóstico y brindar la información necesaria en relación con la atención primaria y el seguimiento de los pacientes.

Nanometallic structures efficiently convert light to surface plasmon-polaritons (SPPs) localized to ultra-small volumes. Such structures provide highly enhanced fields and are of interest in applications involving SPP-enhanced nonlinear optics. We report the design and construction of a spontaneous Raman microscope augmented with in situ reflectance measurement capabilities, and demonstrate its use for nonlinear plasmonics. The structures investigated consist of rectangular gold nanoantennas on graphene on a SiO_2/Si substrate. Specifically, SPP-enhanced Raman scattering from graphene is investigated using nanoantennas that are spectrally aligned with the Stokes wavelength of the graphene 2D peak. We use the microscope to demonstrate Raman scattering enhancement in graphene based on plasmonic resonant enhancement of the Stokes emission, where a maximum cross-sectional gain of ∼500 per antenna was measured. We also measure the reflectance response of nanoantenna structures of different dimensions (length, width) to determine how the resonant wavelength shifts with dimensions and ensure spectral alignment with the Stokes wavelengths of interest.

Gratings capable of incoupling an incident Gaussian beam into long-range surface plasmon polaritons (LRSPPs), propagating along a thin narrow Au stripe on a low-index cladding (fluoropolymer), or on a truncated 1D photonic crystal as a Bloch LRSPP, are investigated for potential biosensing application. The gratings are optimized, initially, through 2D modeling using the vectorial finite element method. Different 3D grating designs are then investigated through 3D modeling using the vectorial finite difference time domain method, including wide gratings on adiabatic and nonadiabatic flared stripes. Wide gratings on flared stripes have a larger area enabling size matching and coupling to larger incident beams, which facilitates optical alignments. We also investigate the effects of changing the size of the beam incident on the structures. Incoupling efficiencies of up to 25% at λ_0=1310 are predicted for optimal gratings—such coupling efficiencies are among the highest reported to date for a structure of this kind. Similar grating designs are also examined as outcoupling structures, capable of coupling (Bloch) LRSPPs into a perpendicularly emerging Gaussian beam. The absorptance, reflectance, and transmittance of the structure were also calculated. Structures were fabricated on a multilayer wafer supporting Bloch LRSPPs to verify design concepts.

Long-range surface plasmon polariton waveguides consisting of Au stripes integrated with input and output grating couplers embedded in thick Cytop claddings are proposed and demonstrated experimentally. Under the right conditions, grating couplers enable broadside (top) coupling with good efficiency while producing a low level of background light. The scheme does not require high-quality input and output edge facets, and it simplifies optical alignments. We demonstrate coupling using a cleaved bow-tie fiber and a lensed fiber, and we determine the grating coupling efficiencies in both cases over a broad operating wavelength range. The lensed fiber produces a better overlap with the long-range surface plasmon mode of interest and thus results in a better coupling efficiency with essentially no background light as observed on an infrared camera. The measurements are compared with theoretical results obtained using a realistic model of the structures, including out-of-plane curvature in the grating profile resulting from our fabrication process. The coupling scheme along with the surface plasmon waveguides hold strong potential for biosensing applications.

In this paper we discuss the optical response of laser-written plasmonic colours on silver coated via the atomic layer deposition of alumina. These colours are due to nanoparticles distributed on a flat surface and on a surface with periodic topographical features (i.e. ripples). The colours are observed to shift with increasing alumina film thickness. The colours produced by surfaces with ripples recover their original vibrancy and hue after the deposition of film of thickness ~60 nm, while colours arising from flat surfaces gradually fade and never recover. Analysis of the surfaces identifies periodic topographical features to be responsible for this behaviour. Finite-difference time-domain simulations unravel the role played by the alumina thickness in colour formation and confirm the rotations and recovery of colours for increasing alumina thickness. The coloured surfaces were evaluated for applications in colourimetric and radiometric sensing showing large sensitivities of up to 3.06/nm and 3.19 nm/nm, respectively. The colourimetric and radiometric sensitivities are observed to be colour dependent.

The symmetry of achiral metasurfaces suggests selective absorption is nonexistent when irradiated either by circularly polarized Gaussian or twisted light beams carrying orbital angular momentum (OAM). In chiral metasurfaces, the lack of symmetry leads to differential absorption when probed with chiral light either in the form of circular polarization (circular dichroism) or helical phase fronts (helical dichroism). Here, we demonstrate differential absorption of asymmetric twisted light beams, known as helical dichroism, which exist in an array and a single achiral structure and can be controlled. When extended to chiral structures, these asymmetrical chiral light modes enable to enhance and tune chiroptical sensitivity. Our technique offers more control parameters than just changing the OAM value, as presented in previous studies. Selective response to asymmetric helical light beams is qualitatively explained in terms of induced multipole moments. The presence of dichroism in achiral nanostructures offers a significant fabrication advantage over complex chiral structures and enables the development of next-generation plasmonic-based chiroptical spectroscopy and molecular sensing.

The objective of this study was to estimate the prevalence of Treponema pallidum, Trypanosoma cruziand Human immunodeficiency virus1 (HIV-1) in five Amerindian populations of Argentina. A retrospective study was conducted among 857 Amerindian populations (112 Kollas, 298 Mbyá-guaraníes, 79 Sagua Huarpes, 368 Wichis) from 2007 to 2010. Screening and confirmation of T. pallidum, T. cruziand HIV-1 were performed. T. pallidumand T. cruziinfections were detected in all communities with an overall prevalence rate of 4.2% and 16.8%, respectively. Although HIV was not detected, syphilis and Chagas’ disease represent a challenge for the health care system and the reinforcement of public health strategies is necessary considering the socioeconomic isolation of these populations.

Topological operations around exceptional points1–8—time-varying system configurations associated with non-Hermitian singularities—have been proposed as a robust approach to achieving far-reaching open-system dynamics, as demonstrated in highly dissipative microwave transmission3and cryogenic optomechanical oscillator4experiments. In stark contrast to conventional systems based on closed-system Hermitian dynamics, environmental interferences at exceptional points are dynamically engaged with their internal coupling properties to create rotational stimuli in fictitious-parameter domains, resulting in chiral systems that exhibit various anomalous physical phenomena9–16. To achieve new wave properties and concomitant device architectures to control them, realizations of such systems in application-abundant technological areas, including communications and signal processing systems, are the next step. However, it is currently unclear whether non-Hermitian interaction schemes can be configured in robust technological platforms for further device engineering. Here we experimentally demonstrate a robust silicon photonic structure with photonic modes that transmit through time-asymmetric loops around an exceptional point in the optical domain. The proposed structure consists of two coupled silicon-channel waveguides and a slab-waveguide leakage-radiation sink that precisely control the required non-Hermitian Hamiltonian experienced by the photonic modes. The fabricated devices generate time-asymmetric light transmission over an extremely broad spectral band covering the entire optical telecommunications window (wavelengths between 1.26 and 1.675 micrometres). Thus, we take a step towards broadband on-chip optical devices based on non-Hermitian topological dynamics by using a semiconductor platform with controllable optoelectronic properties, and towards several potential practical applications, such as on-chip optical isolators and non-reciprocal mode converters. Our results further suggest the technological relevance of non-Hermitian wave dynamics in various other branches of physics, such as acoustics, condensed-matter physics and quantum mechanics.

Plasmonic antennas can enhance the intensity of a nanojoule laser pulse by localizing the electric field in their proximity. It has been proposed that the field can become strong enough to convert the fundamental laser frequency into high-order harmonics through an extremely nonlinear interaction with gas atoms that occupy the nanoscopic volume surrounding the antennas. However, the small number of gas atoms that can occupy this volume limits the generation of high harmonics. Here we use an array of monopole nano-antennas to demonstrate plasmon-assisted high-harmonic generation directly from the supporting crystalline silicon substrate. The high density of the substrate compared with a gas allows macroscopic buildup of harmonic emission. Despite the sparse coverage of antennas on the surface, harmonic emission is ten times brighter than without antennas. Imaging the high-harmonic radiation will allow nanometre and attosecond measurement of the plasmonic field thereby enabling more sensitive plasmon sensors while opening a new path to extreme-ultraviolet-frequency combs.

At an OSA Incubator Meeting, scientists and engineers explored the opportunities and emerging applications enabled by controlling light at subwavelength scale.

We propose and investigate a Schottky contact detector where the contact metal is a nanoscale metal stripe waveguide supporting surface plasmons with strong localization along the Schottky contact. We consider Au for the metal stripe, p-doped silicon for the semiconductor, operation in the infrared (at λ_0=1550  nm), and internal photoemission as the sub-bandgap detection mechanism. We find that the main surface plasmon mode of operation of the Au stripe exhibits diverging real and imaginary parts of n_eff with decreasing stripe dimensions, commensurate with increasing confinement. The mode fields are tightly confined to the immediate vicinity of the stripe within a very small area. Coupling efficiencies, responsivities, dark currents, and minimum detectable powers are computed. An application envisaged for such nanoscale “point detectors” is optical beam scanning, motivated by the very small area of the photodetector stripe mode relative to, e.g., a Gaussian beam (∼500× smaller), such that its field distribution approximates a Dirac delta function in comparison, and by the photocurrent originating primarily from selective absorption of the photodetector stripe mode. The proposed application was verified through numerical simulation, demonstrating that a nanoscale “point detector” can scan a tightly focused Gaussian beam (2.5 μm diameter at λ_0=1550  nm) with good resolution and signal to noise.

A triple-output Mach–Zehnder interferometric sensor operating with long-range surface plasmon–polaritons at free-space wavelengths near 1310 nm was constructed by etching a microfluidic channel through the top cladding (Cytop) of one arm of the interferometer to expose the Au stripe embedded therein. Optical bulk (refractometric) sensing was conducted by sequentially flowing sample solutions with different refractive indices through the microfluidic channel and measuring the optical powers of the three outputs, which responded sinusoidally and were separated by ∼2π/3  rad as expected in theory. Three detection schemes are analyzed and compared, demonstrating that the device benefits from a 3× larger dynamic range and the ability to suppress common perturbations relative to its single-output counterpart, thus improving the detection limit. The device is promising for biosensing applications.

A plasmonic metasurface for the enhancement of nonlinear optical effects is proposed. The metasurface can simultaneously enhance perpendicularly polarized electric fields in the same volume. We illustrate application of the metasurface to the production of Terahertz radiation via the parametric process of difference frequency generation in 4¯3m non-centro symmetric materials, e.g., GaAs, which has a large second-order nonlinear susceptibility. An enhancement over bulk of almost two orders of magnitude near the surface supports the use of the proposed structure for thin-film, surface-based, or chip-based nonlinear optical applications for several crystal classes.

Surface plasmons have raised much interest over the past few decades in part for their potential in biosensing applications. Waveguide Bragg gratings supporting long-range surface plasmon polaritons, constructed by stepping the width of a metal stripe embedded in Cytop, with an etched microfluidic channel to expose the sensing surface, are proposed as biosensors. Several designs are investigated theoretically to evaluate their bulk and surface sensitivities under wavelength interrogation. Detection limits of ∼10^−6  RIU and ∼8  pg/mm^2 are predicted for bulk and surface sensing, respectively, with corresponding figures of merit of ∼1000  RIU^−1 and ∼0.2  nm^−1. Third-order gratings are good choices because they have essentially the same sensitivity as first-order gratings but over a narrower bandwidth, and they are easier to fabricate due to their larger pitch.

AbstractExploiting surface plasmon polaritons to enhance interactions between graphene and light has recently attracted much interest. In particular, nonlinear optical processes in graphene can be dramatically enhanced and controlled by plasmonic nanostructures. This work demonstrates Raman scattering enhancement in graphene based on plasmonic resonant enhancement of the Stokes emission, and compares this mechanism with the conventional Raman enhancement by resonant pump absorption. Arrays of optical nanoantennas with different resonant frequency are utilized to independently identify the effects of each mechanism on Raman scattering in graphene via the measured enhancement factor and its spectral linewidth. We demonstrate that, while both mechanisms offer large enhancement factors (scattering cross-section gains of 160 and 20 for individual nanoantennas, respectively), they affect the graphene Raman spectrum quite differently. Our results provide a benchmark to assess and quantify the role and merit of each mechanism in surface-plasmon-mediated Raman scattering in graphene, and may be employed for design and realization of a variety of graphene optoelectronic devices involving nonlinear optical processes.

A standard single-mode optical fiber, coated with low-index polymer (Cytop), then a thin Au sheath, immersed in fluid, is proposed as a structure for optical (bio)chemical sensing. The highest-order EH_1m cladding modes are found to couple strongly to long- or short-range surface plasmons on the Au sheath, forming coupled modes that are sensitive to the refractive index of the fluid or to a biochemical adlayer formed on the outer surface of the Au sheath. Interrogation of the modes can be achieved with the help of a tilted grating photoinduced into the core of the fiber. We demonstrate experimentally, in this manner, the excitation of these modes, and their use for bulk sensing. Furthermore, negative bulk sensitivity was observed for some leaky modes beyond cutoff.

To understand the pathologic and clinical correlates of patients with chronic meralgia paresthetica (MP) undergoing lateral femoral cutaneous nerve (LFCN) neurectomy.

Silver gratings supporting surface plasmons at 532 nm catalyze the formation of light-emitting solid carbon from ${\rm CO}_2$ gas, revealing a low-energy ${\rm CO}_2$ reduction pathway involving hot electrons. Reversibility and spatial control over the formation of carbon quantum emitters are achieved.